1. Field of the Invention
The present invention relates to exchange catheters for facilitating the exchange of a guiding catheters during catheterization procedures without disturbing the position of a guidewire. More particularly, the present invention relates to such exchange catheters which further facilitate the exchange of femoral sheaths.
2. Description of the Related Art
Catheterization procedures are the foundation of percutaneous transluminal coronary angioplasty (PTCA), which is a procedure used in the treatment of obstructive disorders of the human vascular system. Briefly, PTCA entails inserting a long, tubular guiding catheter through the skin (percutaneous) of a patient into a blood vessel, most commonly the femoral artery, with the aid of an introducer and a femoral sheath. The guiding catheter is advanced through the artery (transluminal) to a point at which the far or distal end of the guiding catheter is positioned near an obstruction or stenotic lesion in a blood vessel of the heart (coronary). A guidewire is then inserted though the guiding catheter, exiting out a port in the guiding catheter distal end, and is advanced through the lesion. An interventional device such as a balloon catheter is then inserted through the guiding catheter over the guidewire to treat the lesion (angioplasty).
During PTCA, in order to minimize trauma to the patient, the guiding catheter and, accordingly, the interventional device should be as small as possible while still being able to treat the lesion. However, it may be determined during PTCA that a larger interventional device is needed to perform the angioplasty successfully. Therefore, the guiding catheter may need to be replaced with a larger guiding catheter which is able to accommodate a larger interventional device. However, this exchange of guiding catheters must take place most preferably without disturbing the position of the guidewire within or displacing the guidewire from the stenotic lesion. Additionally, if the guidewire is inadvertently pulled out of or displaced from the stenotic lesion so that the guidewire would need to be advanced through the stenotic lesion again to continue the angioplasty, traumatic complications may occur, with the only option being emergency surgery which is known to have higher morbidity and mortality rates. This is particularly true if the initial treatment caused vessel spasm or abrupt closure of the blood vessel at the stenotic lesion.
Numerous techniques have been developed for the exchange of guiding catheters while attempting not to disturb the position of the guidewire within the stenotic lesion. Although many of these techniques address the maintenance of guidewire position, they do not address more specific areas of concern, e.g., femoral sheath exchange capability or supportive configurations for facilitating catheter exchange.
Accordingly, due to the delicate nature of catheterization procedures there is a need in the art of exchange catheters for an exchange catheter which facilitates the exchange of one guiding catheter with a larger guiding catheter without disturbing the position of a guidewire within a stenotic lesion. Furthermore, there is a need in the art of exchange catheters for an exchange catheter which also facilitates the exchange of femoral sheaths so as to minimize trauma to a patient and to improve the success of catheterization procedures.